“'HTMLDocument' is undefined” in IE8

Question

I've been looking around, and everywhere it is said that IE8 do have HTMLDocument and Element classes. Unfortunately when I'm trying to access it, all I get is:

"'HTMLDocument' is undefined"
"'HTMLElement' is undefined"
"'Element' is undefined"
"'Document' is undefined"

I've been suspecting that it's consoles fault, but same thing happens when I load it from the script and prototype for ie Array does exist normally.

Could it be that I'm trying access it in the wrong way? I'm using:

typeof HTMLDocument.prototype.getElementsByClassName != 'function'

Answer 1

I am not sure, but may be, that's because you're in compatibility mode.

You can make something like:

var elementPrototype = typeof HTMLElement !== "undefined" 
        ? HTMLElement.prototype : Element.prototype;

But this will work for IE7+ .

Answer 2

Ok, I found it. IE sets itself to Quirks mode for the page I've been testing it on. Unfortunately I can't set document mode in this case, so adding my own getElementsByClassName is a lost cause...

For those that can edit html document they are working on, add this meta tag to assure IE8 will act as IE8:

<meta http-equiv="X-UA-Compatible" content="IE=8">

Answer 3

var hasClass = function (el, searchClass) {
    return el.className.test(new RegExp('(\\s|^)' + searchClass + '(\\s|$)'));
};

You can't add methods to HTMLElement.prototype in older versions of IE.

You can always add this to the Object.prototype object but it's frowned on

Demo